feat: lnd_rest allow self payments (#2760)

* Update lndrest.py

- added the ability to receive self payments on the node

[issue] You have to enable circular payment on lnd.conf. Note that lnd.conf doesn't allow allow_self_payment parameter, that is why is necessary to define that on transaction.

* feat: add LND rest `"allow_self_payment"` option

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Co-authored-by: Vlad Stan <stan.v.vlad@gmail.com>

lnbits/static/js/components/lnbits-funding-sources.js

@@ -64,7 +64,8 @@ window.app.component('lnbits-funding-sources', {
             lnd_rest_cert: 'Certificate',
             lnd_rest_macaroon: 'Macaroon',
             lnd_rest_macaroon_encrypted: 'Encrypted Macaroon',
-            lnd_rest_route_hints: 'Enable Route Hints'
+            lnd_rest_route_hints: 'Enable Route Hints',
+            lnd_rest_allow_self_payment: 'Allow Self Payment'
           }
         ],
         [